Myxobolus honghuensis n. sp. (Myxosporea: Bivalvulida) parasitizing the pharynx of allogynogenetic gibel carp Carassius auratus gibelio (Bloch) from Honghu Lake, China

Abstract

Myxobolus honghuensis n. sp. is described from allogynogenetic gibel carp Carassius auratus gibelio (Bloch), during a survey of myxosporean parasites in Honghu Lake, Hubei Province, China. It is characterized by the presence of round plasmodia of 5-12 mm in diameter in the pharynx of host. Mature spores of M. honghuensis were pyriform in frontal view and anterior pointed with bluntly round posterior, they measured 16.9 ± 0.5 (15.1-19.5) μm long, 10.4 ± 0.4 (9.0-11.3) μm wide, and 8.4 ± 0.4 (7.9-9.1) μm thick. Two polar capsules were pyriform and slightly unequal with larger polar capsule 8.4 ± 0.4 (7.6-10.2) μm × 3.9 ± 0.2 (3.0-4.5) μm and smaller capsule 7.9 ± 0.2 (7.0-9.3) μm × 3.7 ± 0.3 (2.8-4.1) μm. Polar filaments coiled with seven to eight turns. Both morphology and DNA sequence data revealed that M. honghuensis n. sp. was distinct from other described Myxobolus species. Phylogenetic analysis placed M. honghuensis n. sp. in a clade of gill-infecting myxobolids.

Morphological and molecular characterization of Myxobolus mucosus sp. n. (Myxosporea: Myxobolidae) with basifilamental sporulation in two cyprinid fishes, Rutilus rutilus (L.) and Leuciscus leuciscus (L.) in Russia

“…However, it is still ambiguous to what extent of sequence variation can be determined to be intraspecific or interspecific. Myxobolus dujardini was reported to have as much as 3.6 % intraspecific sequence variation (Molnár et al 2006), while Myxobolus honghuensis is 98.5 % similar to Myxobolus ampulicapsulatus (Liu et al 2012). Molecular markers with high resolution probably give better insight into the process of species differentiation of myxosporean parasites.…”

Three actinosporean types (Myxozoa) from the oligochaete Branchiura sowerbyi in China

“…During the investigation, Myxobolus cultus Yokoyama, Ogawa & Wakabayashi, 1995 in the gill and M. honghuensis Liu, Whipps, Gu, Zeng & Huang, 2012 in the pharynx of crucian carps also were detected from the same pond, from where the oligochaetes were collected. Besides, another five myxospores were found from nearby crucian carp ponds: Thelohanellus wuhanensis Xiao and Chen, 1993, …”

“…Jiangsu Province is a main crucian carp culture zone, where the culture area is almost 50,000 ha. Since the 1990s, infection with myxosporeans, especially Myxobolus honghuensis Liu, Whipps, Gu, Zeng & Huang, 2012 parasitic in the pharynx, which was firstly reported as Myxobolus ampullicapsulatus, and Myxobolus wulii Landsberg & Lom, 1991 in the hepatopancreas have caused serious disease of the reared crucian carp (Zhang et al 2010;Xi et al 2011;Liu et al 2012). Thus, studies on the pathogens identification, epidemiology, and life cycle would provide valuable information to design effective control measures against myxozoan diseases.…”

Thelohanellus wangi n. sp. (Myxozoa, Myxosporea), a new gill parasite of allogynogenetic gibel carp (Carassius auratus gibelio Bloch) in China, causing severe gill myxosporidiosis

“…Reducing the severe negative effects of the myxosporidiosis on this commercially important species has been considered a priority in China. Until now, more than 40 myxosporean species belonging to Myxobolus, Thelohanellus, Hennegua, Sphaerospora, Myxidium, Myxobilatus, Hoferellus, Chloromyxum, Zschokkella and Unicauda genera have been found in allogynogenetic gibel carp, with high diversity of infection habitats (Xiao 1988;Chen and Ma 1998;Zhang et al 2006;Zhao et al 2008;Zhang et al 2010a, b;Liu et al 2012;Zhao et al 2013;Liu et al 2014a, b;Ye et al 2014). These myxosporean parasites can infect almost all stages of a whole culture cycle of this fish.…”

“…Some of them show high bias of infection to fish size. For instance, Thelohanellus wuhanensis exclusively infects the fry of nursery stage, but Myxobolus turpisrotundus, Myxobolus honghuensis, and Myxobolus ampullicapsulatus are obligate parasites of the fattening fish (Wang et al 2001;Zhang et al 2010b;Xi et al 2011;Liu et al 2012).…”